[Formulajones]

I've been pushing the 91 pump gas for years here in Arizona, same junk California has. I'm running an 11:1 engine with iron heads fine on it, it likes 36 degrees of timing where it made best power, my bird is 10.13:1 with it's factory iron heads fine on it with best power at 34 degrees, both of these cars are daily driven.
We actually have aluminum headed cars that are a pinch more conservative on compression which is the opposite of what you would expect. One being 10.2:1 that runs with 38 degrees of timing and another with 10.84:1 that likes 34 degrees of timing. Got a couple more with iron heads that have over 10:1 compression and currently building another aluminum headed engine that should end up with compression somewhere in the mid 10's.

Everything runs on the 91 cat pee we have available.